The limited-angle DC torque motor is a servo motor that can directly drive the load for rapid motion and accurate positioning within a certain range of angles. In a limited-angle mechanism, the drive load can only swing within a limited range of angles, while the drive motor can rotate 360° forward and reverse.Then limit the drive load to swing within a limited range of angles through a limit switch or through a gear and limit switch.This type of drive motor can also use a limited-angle motor.

Limited-angle motors have two types of swing magnetic field type and swing armature type.Because the motor rotor itself can only oscillate within a limited range of angles, even a swivel armature type limited-angle motor does not need to pass the brush slip ring, and the current is directly introduced into the armature, so the limited-angle motor is also a brushless DC motor. It is simpler than the general electronically commutated brushless motor, and it will not be troubled by brushes like a brushed motor.

The limited-angle torque motor is mainly used in some high-precision control systems, such as gyroscope stabilization platform, infrared imaging, military aiming, driving of pointers and stylus pens in industrial automation instruments. According to the torque motor, the position servo system has the characteristics of large output, wide frequency band, high positioning accuracy, small size and light weight. The system can be used to directly drive loads within a limited angle in high-precision electrical servo systems such as electro-hydraulic servo valves, servo actuation, robot joints, and radar antennas.